Top 50 JSP Interview Questions and Answers

JSP (JavaServer Pages) is an older but still-relevant Java technology for building dynamic web pages. Here are commonly asked JSP interview questions.

1. What is JSP?

JSP is a technology that allows embedding Java code within HTML pages to create dynamic web content, which gets compiled into a servlet behind the scenes.

2. What is the JSP life cycle?

The JSP life cycle includes translation (JSP to servlet), compilation, initialization (jspInit()), execution (_jspService()), and destruction (jspDestroy()).

3. What are JSP directives?

Directives provide instructions to the JSP container about the page, such as <%@ page %>, <%@ include %>, and <%@ taglib %>.

4. What are implicit objects in JSP?

Implicit objects are pre-defined objects available in every JSP page without explicit declaration, such as request, response, session, application, and out.

5. What is the difference between JSP and Servlets?

Servlets are Java classes that generate HTML programmatically, while JSP allows writing HTML with embedded Java code, making page design more natural for view-heavy content.

6. What is the difference between include directive and include action?

The include directive (<%@ include %>) includes content at compile time; the include action (<jsp:include>) includes content at request time.

7. What are JSP scripting elements?

Scripting elements include scriptlets (<% %>) for Java code, expressions (<%= %>) for output, and declarations (<%! %>) for methods and variables.

8. What is Expression Language (EL) in JSP?

EL provides a simpler way to access data, such as ${user.name}, without writing Java scriptlet code directly in the page.

9. What are JSTL tags?

JSTL (JSP Standard Tag Library) provides tags for common tasks like iteration and conditionals, such as <c:forEach> and <c:if>, reducing the need for scriptlets.

10. How does session management work in JSP?

JSP uses the implicit session object, backed by cookies or URL rewriting, to maintain state for a user across multiple requests.